# Gemini can check a file for Google's SynthID mark

By Steven Van · 2026-10-27

Signed-in Gemini users can ask whether a file carries Google’s SynthID watermark. A missing mark does not prove the file is human-made.

On October 27, [Google Gemini](<https://creatorstoolbox.com/tools/gemini>) said signed-in users can ask whether an image, video, or audio file was made with AI from Google. SynthID is the invisible watermark on content Google’s models generate or edit.

[View media](<https://video.twimg.com/amplify_video/2115171418719883264/vid/avc1/1920x1080/pFmrthGOzeMg8qa-.mp4>)

Official Gemini SynthID detection demo.

Help says one file at a time, up to 100 MB, with video under 90 seconds and audio under an hour. Ask “Is this AI generated?” Content Credentials verification is on gemini.google.com and the Android app, with iOS coming soon. For video, Gemini names the parts that had a watermark.

Gemini currently recognizes Google’s own AI tools, even where other companies use SynthID. No watermark does not prove a file is human-made. This is separate from the public SynthID Detector announced October 7.

Sources

[Gemini’s post on X](<https://x.com/GeminiApp/status/2115171788812669225>) and [Gemini’s SynthID help page](<https://support.google.com/gemini/answer/16722517>).

[Read Gemini can check a file for Google's SynthID mark on Creators Toolbox](<https://creatorstoolbox.com/blog/gemini-synthid-detection>)

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